media_observer.h revision 2a99a7e74a7f215066514fe81d2bfa6639d9eddd 
1// Copyright (c) 2012 The Chromium Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5#ifndef CONTENT_PUBLIC_BROWSER_MEDIA_OBSERVER_H_
6#define CONTENT_PUBLIC_BROWSER_MEDIA_OBSERVER_H_
7
8#include "content/public/browser/media_request_state.h"
9#include "content/public/common/media_stream_request.h"
10
11namespace content {
12
13// An embedder may implement MediaObserver and return it from
14// ContentBrowserClient to receive callbacks as media events occur.
15class MediaObserver {
16 public:
17  // Called when capture devices are opened. The observer can call
18  // |close_callback| to stop the stream.
19  virtual void OnCaptureDevicesOpened(
20      int render_process_id,
21      int render_view_id,
22      const MediaStreamDevices& devices,
23      const base::Closure& close_callback) = 0;
24
25  // Called when the opened capture devices are closed.
26  virtual void OnCaptureDevicesClosed(
27      int render_process_id,
28      int render_view_id,
29      const MediaStreamDevices& devices) = 0;
30
31  // Called when a audio capture device is plugged in or unplugged.
32  virtual void OnAudioCaptureDevicesChanged(
33      const MediaStreamDevices& devices) = 0;
34
35  // Called when a video capture device is plugged in or unplugged.
36  virtual void OnVideoCaptureDevicesChanged(
37      const MediaStreamDevices& devices) = 0;
38
39  // Called when a media request changes state.
40  virtual void OnMediaRequestStateChanged(
41      int render_process_id,
42      int render_view_id,
43      const MediaStreamDevice& device,
44      MediaRequestState state) = 0;
45
46  // Called when an audio stream is played or paused.
47  virtual void OnAudioStreamPlayingChanged(
48      int render_process_id,
49      int render_view_id,
50      int stream_id,
51      bool playing) = 0;
52
53 protected:
54  virtual ~MediaObserver() {}
55};
56
57}  // namespace content
58
59#endif  // CONTENT_PUBLIC_BROWSER_MEDIA_OBSERVER_H_
60